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1.
Cell ; 174(5): 1158-1171.e19, 2018 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-30057110

RESUMO

Characterizing cell surface receptors mediating viral infection is critical for understanding viral tropism and developing antiviral therapies. Nevertheless, due to challenges associated with detecting protein interactions on the cell surface, the host receptors of many human pathogens remain unknown. Here, we build a library consisting of most single transmembrane human receptors and implement a workflow for unbiased and high-sensitivity detection of receptor-ligand interactions. We apply this technology to elucidate the long-sought receptor of human cytomegalovirus (HCMV), the leading viral cause of congenital birth defects. We identify neuropilin-2 (Nrp2) as the receptor for HCMV-pentamer infection in epithelial/endothelial cells and uncover additional HCMV interactors. Using a combination of biochemistry, cell-based assays, and electron microscopy, we characterize the pentamer-Nrp2 interaction and determine the architecture of the pentamer-Nrp2 complex. This work represents an important approach to the study of host-pathogen interactions and provides a framework for understanding HCMV infection, neutralization, and the development of novel anti-HCMV therapies.


Assuntos
Infecções por Citomegalovirus/metabolismo , Citomegalovirus/fisiologia , Neuropilina-2/metabolismo , Receptores Virais/metabolismo , Anticorpos Neutralizantes/química , Membrana Celular/metabolismo , Células Endoteliais/metabolismo , Células Epiteliais/metabolismo , Mapeamento de Epitopos , Feminino , Células HEK293 , Humanos , Conformação Proteica , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus
2.
Proc Natl Acad Sci U S A ; 119(2)2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34987100

RESUMO

Myeloid lineage cells such as macrophages and dendritic cells (DCs), targeted by HIV-1, are important vehicles for virus dissemination through the body as well as viral reservoirs. Compared to activated lymphocytes, myeloid cells are collectively more resistant to HIV-1 infection. Here we report that NRP-1, encoding transmembrane protein neuropilin-1, is highly expressed in macrophages and DCs but not CD4+ T cells, serving as an anti-HIV factor to inhibit the infectivity of HIV-1 progeny virions. Silencing NRP-1 enhanced the transmission of HIV-1 in macrophages and DCs significantly and increased the infectivity of the virions produced by these cells. We further demonstrated that NRP-1 was packaged into the progeny virions to inhibit their ability to attach to target cells, thus reducing the infectivity of the virions. These data indicate that NRP-1 is a newly identified antiviral protein highly produced in both macrophages and DCs that inhibit HIV-1 infectivity; thus, NRP-1 may be a novel therapeutic strategy for the treatment of HIV-1 infection.


Assuntos
Infecções por HIV/tratamento farmacológico , Células Mieloides/metabolismo , Neuropilina-1/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linhagem Celular , Células Dendríticas/metabolismo , HIV-1 , Humanos , Macrófagos/metabolismo , Macrófagos/virologia , Vírion/metabolismo , Replicação Viral/efeitos dos fármacos
3.
Proc Natl Acad Sci U S A ; 119(35): e2200960119, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35951647

RESUMO

Although increasing evidence confirms neuropsychiatric manifestations associated mainly with severe COVID-19 infection, long-term neuropsychiatric dysfunction (recently characterized as part of "long COVID-19" syndrome) has been frequently observed after mild infection. We show the spectrum of cerebral impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, ranging from long-term alterations in mildly infected individuals (orbitofrontal cortical atrophy, neurocognitive impairment, excessive fatigue and anxiety symptoms) to severe acute damage confirmed in brain tissue samples extracted from the orbitofrontal region (via endonasal transethmoidal access) from individuals who died of COVID-19. In an independent cohort of 26 individuals who died of COVID-19, we used histopathological signs of brain damage as a guide for possible SARS-CoV-2 brain infection and found that among the 5 individuals who exhibited those signs, all of them had genetic material of the virus in the brain. Brain tissue samples from these five patients also exhibited foci of SARS-CoV-2 infection and replication, particularly in astrocytes. Supporting the hypothesis of astrocyte infection, neural stem cell-derived human astrocytes in vitro are susceptible to SARS-CoV-2 infection through a noncanonical mechanism that involves spike-NRP1 interaction. SARS-CoV-2-infected astrocytes manifested changes in energy metabolism and in key proteins and metabolites used to fuel neurons, as well as in the biogenesis of neurotransmitters. Moreover, human astrocyte infection elicits a secretory phenotype that reduces neuronal viability. Our data support the model in which SARS-CoV-2 reaches the brain, infects astrocytes, and consequently, leads to neuronal death or dysfunction. These deregulated processes could contribute to the structural and functional alterations seen in the brains of COVID-19 patients.


Assuntos
Encéfalo , COVID-19 , Viroses do Sistema Nervoso Central , SARS-CoV-2 , Astrócitos/patologia , Astrócitos/virologia , Encéfalo/patologia , Encéfalo/virologia , COVID-19/complicações , COVID-19/patologia , Viroses do Sistema Nervoso Central/etiologia , Viroses do Sistema Nervoso Central/patologia , Humanos , Síndrome de COVID-19 Pós-Aguda
4.
Immunology ; 172(2): 226-234, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38409805

RESUMO

Group 2 innate lymphoid cells (ILC2s) play critical roles in driving the pathogenesis of allergic airway inflammation. The mechanisms underlying the regulation of ILC2s remain to be fully understood. Here, we identified neuropilin-1 (NRP1) as a surface marker of ILC2s in response to IL-33 stimulation. NRP1 was abundantly expressed in ILC2s from lung under steady state, which was significantly reduced upon IL-33 stimulation. ILC2s with high expression of NRP1 (NRP1high) displayed lower response to IL-33, as compared with NRP1low ILC2s. Transcriptional profiling and flow cytometric analysis showed that downregulation of AKT-mTOR signalling participated in the diminished functionality of NRP1high ILC2s. These observations revealed a potential role of NRP1 in ILC2s responses under allergic inflammatory condition.


Assuntos
Regulação para Baixo , Imunidade Inata , Interleucina-33 , Linfócitos , Neuropilina-1 , Transdução de Sinais , Interleucina-33/metabolismo , Interleucina-33/imunologia , Animais , Neuropilina-1/metabolismo , Neuropilina-1/genética , Camundongos , Linfócitos/imunologia , Linfócitos/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Camundongos Endogâmicos C57BL
5.
Am J Transplant ; 24(2): 213-221, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37739346

RESUMO

One concern about the use of normothermic regional perfusion (NRP) in controlled donation after the circulatory determination of death (cDCD) is that the brain may be perfused. We aimed to demonstrate that certain technical maneuvers preclude such brain perfusion. A nonrandomized trial was performed on cDCD donors. In abdominal normothermic regional perfusion (A-NRP), the thoracic aorta was blocked with an intra-aortic occlusion balloon. In thoracoabdominal normothermic regional perfusion (TA-NRP), the arch vessels were clamped and the cephalad ends vented to the atmosphere. The mean intracranial arterial blood pressure (ICBP) was invasively measured at the circle of Willis. Ten cDCD donors subject to A-NRP or TA-NRP were included. Mean ICBP and mean blood pressure at the thoracic and the abdominal aorta during the circulatory arrest were 17 (standard deviation [SD], 3), 17 (SD, 3), and 18 (SD, 4) mmHg, respectively. When A-NRP started, pressure at the abdominal aorta increased to 50 (SD, 13) mmHg, while the ICBP remained unchanged. When TA-NRP was initiated, thoracic aorta pressure increased to 71 (SD, 18) mmHg, but the ICBP remained unmodified. Recorded values of ICBP during NRP were 10 mmHg. In conclusion, appropriate technical measures applied during NRP preclude perfusion of the brain in cDCD. This study might help to expand NRP and increase the number of organs available for transplantation.


Assuntos
Preservação de Órgãos , Obtenção de Tecidos e Órgãos , Humanos , Morte , Sobrevivência de Enxerto , Preservação de Órgãos/métodos , Perfusão/métodos , Estudos Prospectivos , Doadores de Tecidos
6.
Am J Transplant ; 24(7): 1127-1131, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38514015

RESUMO

As an alternative to static cold storage (SCS), advanced perfusion techniques such as normothermic regional perfusion and ex-situ perfusion (normothermic or hypothermic) have emerged as a way to improve the ischemic injury suffered by donation after circulatory death (DCD) livers. Multiple studies have been published that have demonstrated superior post-DCD liver transplant outcomes when using advanced perfusion compared with SCS. In particular, these studies have shown lower rates of ischemic cholangiopathy with advanced perfusion. In addition to the improved post-liver transplant outcomes, studies have also demonstrated higher rates of liver utilization from DCD donors when advanced perfusion is used compared with SCS. Given the high rates of graft loss in patients who develop ischemic cholangiopathy, the significant reduction seen in DCD donor livers that have undergone advanced perfusion represents a key step in more broad utilization of these livers. With such compelling evidence from multiple trials, it seems reasonable to ask the question: should advanced perfusion be the standard of care for DCD liver transplant?


Assuntos
Transplante de Fígado , Preservação de Órgãos , Perfusão , Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Humanos , Preservação de Órgãos/métodos , Perfusão/métodos , Padrão de Cuidado , Obtenção de Tecidos e Órgãos/normas , Obtenção de Tecidos e Órgãos/métodos , Doadores de Tecidos/provisão & distribuição
7.
Am J Transplant ; 24(10): 1803-1815, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38521350

RESUMO

Donation after circulatory death (DCD) could account for the largest expansion of the donor allograft pool in the contemporary era. However, the organ yield and associated costs of normothermic regional perfusion (NRP) compared to super-rapid recovery (SRR) with ex-situ normothermic machine perfusion, remain unreported. The Organ Procurement and Transplantation Network (December 2019 to June 2023) was analyzed to determine the number of organs recovered per donor. A cost analysis was performed based on our institution's experience since 2022. Of 43 502 donors, 30 646 (70%) were donors after brain death (DBD), 12 536 (29%) DCD-SRR and 320 (0.7%) DCD-NRP. The mean number of organs recovered was 3.70 for DBD, 3.71 for DCD-NRP (P < .001), and 2.45 for DCD-SRR (P < .001). Following risk adjustment, DCD-NRP (adjusted odds ratio 1.34, confidence interval 1.04-1.75) and DCD-SRR (adjusted odds ratio 2.11, confidence interval 2.01-2.21; reference: DBD) remained associated with greater odds of allograft nonuse. Including incomplete and completed procurement runs, the total average cost of DCD-NRP was $9463.22 per donor. By conservative estimates, we found that approximately 31 donor allografts could be procured using DCD-NRP for the cost equivalent of 1 allograft procured via DCD-SRR with ex-situ normothermic machine perfusion. In conclusion, DCD-SRR procurements were associated with the lowest organ yield compared to other procurement methods. To facilitate broader adoption of DCD procurement, a comprehensive understanding of the trade-offs inherent in each technique is imperative.


Assuntos
Preservação de Órgãos , Transplante de Órgãos , Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Humanos , Obtenção de Tecidos e Órgãos/economia , Feminino , Masculino , Doadores de Tecidos/provisão & distribuição , Pessoa de Meia-Idade , Transplante de Órgãos/economia , Adulto , Preservação de Órgãos/métodos , Preservação de Órgãos/economia , Perfusão , Coleta de Tecidos e Órgãos/economia , Coleta de Tecidos e Órgãos/métodos , Morte Encefálica , Estudos Retrospectivos , Seguimentos , Prognóstico
8.
Eur J Nucl Med Mol Imaging ; 51(7): 1826-1840, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38319321

RESUMO

PURPOSE: Neuropilin-1 (NRP-1) is a multifunctional protein involved in a variety of biological processes such as angiogenesis, tumorigenesis and immunomodulation. It was usually overexpressed in many cancer cell lines and correlated with poor prognosis of breast cancer. Positron emission tomography (PET) is an advanced imaging technique for detecting the function and metabolism of tumor-associated molecules in real time, dynamically, quantitatively and noninvasively. To improve the level of early diagnosis and evaluate the prognosis of breast cancer, an NRP-1 targeting peptide-based tracer [68 Ga]Ga-NOTA-PEG4-CK2 was designed to sensitively and specifically detect the NRP-1 expression in vivo via PET imaging. METHODS: In silico modeling and microscale thermophoresis (MST) assay were carried out to design the NRP-1 targeting peptide NOTA-PEG4-CK2, and it was further radiolabeled with 68 Ga to prepare the tracer [68 Ga]Ga-NOTA-PEG4-CK2. The radiochemical yield (RCY), radiochemical purity (RCP), molar activity (Am), lipid-water partition coefficient (Log P) and stability of [68 Ga]Ga-NOTA-PEG4-CK2 were assessed. The targeting specificity of the tracer for NRP-1 was investigated by in vitro cellular uptake assay and in vivo PET imaging as well as blocking studies. The sensitivity of the tracer in monitoring the dynamic changes of NRP-1 expression induced by chemical drug was also investigated in vitro and in vivo. Ex vivo biodistribution, autoradiography, western blot, and immunofluorescence staining were also performed to study the specificity of [68 Ga]Ga-NOTA-PEG4-CK2 for NRP-1. RESULTS: [68 Ga]Ga-NOTA-PEG4-CK2 was designed and synthesized with high RCY (> 98%), high stability (RCP > 95%) and high affinity to NRP-1 (KD = 25.39 ± 1.65 nM). In vitro cellular uptake assay showed that the tracer [68 Ga]Ga-NOTA-PEG4-CK2 can specifically bind to NRP-1 positive cancer cells MDA-MB-231 (1.04 ± 0.04% at 2 h) rather than NRP-1 negative cancer cells NCI-H1299 (0.43 ± 0.05%). In vivo PET imaging showed the maximum tumor uptake of [68 Ga]Ga-NOTA-PEG4-CK2 in MDA-MB-231 xenografts (4.16 ± 0.67%ID/mL) was significantly higher than that in NCI-H1299 xenografts (1.03 ± 0.19%ID/mL) at 10 min post injection, and the former exhibited higher tumor-to-muscle uptake ratio (5.22 ± 0.18) than the latter (1.07 ± 0.27) at 60 min post injection. MDA-MB-231 xenografts pretreated with nonradioactive precursor NOTA-PEG4-CK2 showed little tumor uptake of [68 Ga]Ga-NOTA-PEG4-CK2 (1.67 ± 0.38%ID/mL at 10 min post injection). Both cellular uptake assay and PET imaging revealed that NRP-1 expression in breast cancer MDA-MB-231 could be effectively suppressed by SB-203580 treatment and can be sensitively detected by [68 Ga]Ga-NOTA-PEG4-CK2. Ex vivo analysis also proved the high specificity and sensitivity of [68 Ga]Ga-NOTA-PEG4-CK2 for NRP-1 expression in MDA-MB-231 xenografts. CONCLUSION: A promising NRP-1 targeting PET tracer [68 Ga]Ga-NOTA-PEG4-CK2 was successfully prepared. It showed remarkable specificity and sensitivity in monitoring the dynamic changes of NRP-1 expression. Hence, it could provide valuable information for early diagnosis of NRP-1 relevant cancers and evaluating the prognosis of cancer patients.


Assuntos
Radioisótopos de Gálio , Neuropilina-1 , Tomografia por Emissão de Pósitrons , Neuropilina-1/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Animais , Camundongos , Humanos , Linhagem Celular Tumoral , Distribuição Tecidual , Feminino , Compostos Heterocíclicos com 1 Anel/química , Marcação por Isótopo , Peptídeos/química , Regulação Neoplásica da Expressão Gênica , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/química
9.
Amino Acids ; 56(1): 49, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39181965

RESUMO

Inhibitors of the interaction between Neuropilin-1 (NRP-1) and Vascular Endothelial Growth Factor-A165 (VEGF-A165) hold significant promise as therapeutic and diagnostic agents directed against cancers overexpressing NRP-1. In our efforts in this field, a few series of strong and fairly stable peptide-like inhibitors of the general formula Lys(Har)1-Xaa2-Xaa3-Arg4 have been previously discovered. In the current work, we focused on Lys(Har)-Dap/Dab-Pro-Arg sequence. The aim was to examine whether replacing C-terminal Arg with its homologs and mimetics would yield more stable yet still potent inhibitors. Upon considering the results of modelling and other factors, ten novel analogues with Xaa4 = homoarginine (Har), 2-amino-4-guanidino-butyric acid (Agb), 2-amino-3-guanidino-propionic acid (Agp), citrulline (Cit), 4-aminomethyl-phenylalanine [Phe(4-CH2-NH2)] were designed, synthesized and evaluated. Two of the proposed modifications resulted in inhibitors with activity slightly lower [e.g. IC50 = 14.3 µM for Lys(Har)-Dab-Pro-Har and IC50 = 19.8 µM for Lys(Har)-Dab-Pro-Phe(4-CH2-NH2)] than the parent compounds [e.g. IC50 = 4.7 µM for Lys(Har)-Dab-Pro-Arg]. What was a surprise to us, the proteolytic stability depended more on position two of the sequence than on position four. The Dab2-analogues exhibited half-life times beyond 60 h. Our results build up the knowledge on the structural requirements that effective VEGF-A165/NRP-1 inhibitors should fulfil.


Assuntos
Arginina , Neuropilina-1 , Peptidomiméticos , Fator A de Crescimento do Endotélio Vascular , Humanos , Arginina/química , Arginina/análogos & derivados , Neuropilina-1/antagonistas & inibidores , Neuropilina-1/metabolismo , Peptidomiméticos/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Transpl Int ; 37: 13263, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39246548

RESUMO

Liver grafts from controlled donation after circulatory death (cDCD) donors have lower utilization rates due to inferior graft and patient survival rates, largely attributable to the increased incidence of ischemic cholangiopathy, when compared with grafts from brain dead donors (DBD). Normothermic regional perfusion (NRP) may improve the quality of cDCD livers to allow for expansion of the donor pool, helping to alleviate the shortage of transplantable grafts. A systematic review and metanalysis was conducted comparing NRP cDCD livers with both non-NRP cDCD livers and DBD livers. In comparison to non-NRP cDCD outcomes, NRP cDCD grafts had lower rates of ischemic cholangiopathy [RR = 0.23, 95% CI (0.11, 0.49), p = 0.0002], primary non-function [RR = 0.51, 95% CI (0.27, 0.97), p = 0.04], and recipient death [HR = 0.5, 95% CI (0.36, 0.69), p < 0.0001]. There was no difference in outcomes between NRP cDCD donation compared to DBD liver donation. In conclusion, NRP improved the quality of cDCD livers compared to their non-NRP counterparts. NRP cDCD livers had similar outcomes to DBD grafts. This provides further evidence supporting the continued use of NRP in cDCD liver transplantation and offers weight to proposals for its more widespread adoption.


Assuntos
Transplante de Fígado , Perfusão , Humanos , Morte Encefálica , Sobrevivência de Enxerto , Transplante de Fígado/métodos , Preservação de Órgãos/métodos , Perfusão/métodos , Obtenção de Tecidos e Órgãos/métodos , Doadores de Tecidos
11.
Artif Organs ; 48(7): 794-799, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38693706

RESUMO

The American Transplant Congress (ATC) 2023, held in San Diego, California, emerged as a pivotal platform showcasing the latest advancements in organ machine perfusion, a key area in solid organ and tissue transplantation. This year's congress, attended by over 4500 participants, including leading experts, emphasized innovations in machine perfusion technologies across various organ types, including liver, kidney, heart, and lung. A total of 85 abstracts on organ machine perfusion were identified. Noteworthy advancements included the use of normothermic machine perfusion in mitigating ex-situ reperfusion injury in liver transplantation, the potential of biomarkers in assessing organ quality, and the impact of machine perfusion on graft survival and ischemic cholangiopathy incidence. Kidney transplantation saw promising developments in novel preservation methods, such as subzero storage and pulsatile perfusion. Heart and lung sessions revealed significant progress in preservation techniques, including metabolic alterations to extend organ preservation time. The conference also highlighted the growing interest in machine perfusion applications in pediatric transplantation, multi-visceral organ recovery, Vascularized Composite Allotransplantation, and discussions on novel technologies for monitoring and optimizing perfusion protocols. Additionally, ATC 2023 included critical discussions on ethical concerns, legal implications, and the evolving definition of death in the era of machine preservation, illustrating the complex landscape of transplantation science. Overall, ATC 2023 showcased significant strides in machine perfusion and continued its tradition of fostering global knowledge exchange, further cementing machine perfusion's role as a transformative force in improving transplant outcomes and expanding the donor pool.


Assuntos
Preservação de Órgãos , Transplante de Órgãos , Perfusão , Humanos , Preservação de Órgãos/métodos , Preservação de Órgãos/instrumentação , Transplante de Órgãos/métodos , Perfusão/métodos , Perfusão/instrumentação
12.
BMC Urol ; 24(1): 147, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014364

RESUMO

BACKGROUND: Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) has been confirmed to play oncogenic role in many cancers. However, the role and mechanism of IGF2BP2 in bladder cancer (BCa) still deserves to be further revealed. METHODS: The mRNA and protein levels of IGF2BP2 and neuronilin-1 (NRP1) were detected by real-time quantitative PCR (RT-qPCR) and western blot. Cell proliferation, apoptosis, migration and invasion were determined using colony formation assay, EdU assay, CCK8 assay, flow cytometry and transwell assay. Xenograft tumor model was conducted to evaluate the role of IGF2BP2 in vivo. THP-1-M0 macrophages were co-cultured with the condition medium (CM) of BCa cells to induce polarization. M2 macrophage polarization was assessed by detecting the mRNA levels of M2 macrophage markers using RT-qPCR and measuring the proportion of M2 macrophage markers using flow cytometry. Moreover, MeRIP and RIP assay were performed to assess m6A level and the interaction between IGF2BP2 and NRP1. RESULTS: IGF2BP2 and NRP1 were upregulated in BCa tissues and cells. IGF2BP2 knockdown suppressed BCa cell growth and metastasis, as well as inhibited BCa tumor growth. After THP-1-M0 macrophages were co-cultured with the CM of BCa cells, the levels of M2 macrophage markers were markedly enhanced, while this effect was abolished by IGF2BP2 knockdown. IGF2BP2 level was positively correlated with NRP1 level, and it could increase NRP1 mRNA stability. NRP1 overexpression reversed the suppressive effect of IGF2BP2 knockdown on M2 macrophage polarization and BCa cell progression. CONCLUSION: m6A-reader IGF2BP2 enhanced M2 macrophage polarization and BCa cell progression by promoting NRP1 mRNA stability.


Assuntos
Macrófagos , Neuropilina-1 , RNA Mensageiro , Proteínas de Ligação a RNA , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/metabolismo , Humanos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Macrófagos/metabolismo , RNA Mensageiro/metabolismo , Neuropilina-1/genética , Neuropilina-1/metabolismo , Camundongos , Regulação Neoplásica da Expressão Gênica , Animais , Polaridade Celular/fisiologia , Linhagem Celular Tumoral
13.
Neuropathology ; 44(4): 319-330, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38448392

RESUMO

Glioblastoma (GBM) is the most prevalent primary intracranial tumor. Temozolomide (TMZ) is the first-line chemotherapy for GBM. Nonetheless, the development of TMZ resistance has become a main cause of treatment failure in GBM patients. Evidence suggests that neuropilin-1 (NRP-1) silencing can attenuate GBM cell resistance to TMZ. This study aims to determine potential mechanisms by which NRP-1 affects TMZ resistance in GBM. The parental U251 and LN229 GBM cells were exposed to increasing concentrations of TMZ to construct TMZ-resistant GBM cells (U251/TMZ, LN229/TMZ). BALB/c nude mice were injected with U251/TMZ cells to establish the xenograft mouse model. Functional experiments were carried out to examine NRP-1 functions. Western blotting and real-time quantitative polymerase chain reaction were used to evaluate molecular protein and mRNA expression, respectively. Immunohistochemical staining showed NRP-1 and STAT1 expression in mouse tumors. The results showed that NRP-1 was highly expressed in TMZ-resistant cells. Moreover, knocking down NRP-1 attenuated the TMZ resistance of U251/TMZ cells, while upregulating NRP-1 enhanced TMZ resistance of the parental cells. NRP-1 silencing elevated GBM cell sensitivity to TMZ in tumor-bearing mice. Depleting NRP-1 reduced STAT1, p53, and p21 expression in U251/TMZ cells. STAT1 depletion offset NRP-1 silencing evoked attenuation of GBM cell resistance to TMZ. Collectively, our study reveals that NRP-1 enhances TMZ resistance in GBM possibly by regulating the STAT1/p53/p21 axis.


Assuntos
Antineoplásicos Alquilantes , Neoplasias Encefálicas , Resistencia a Medicamentos Antineoplásicos , Glioblastoma , Camundongos Endogâmicos BALB C , Camundongos Nus , Neuropilina-1 , Fator de Transcrição STAT1 , Temozolomida , Proteína Supressora de Tumor p53 , Temozolomida/farmacologia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/metabolismo , Glioblastoma/genética , Animais , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neuropilina-1/metabolismo , Neuropilina-1/genética , Humanos , Fator de Transcrição STAT1/metabolismo , Antineoplásicos Alquilantes/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Camundongos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Am J Bioeth ; 24(6): 27-33, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829586

RESUMO

The introduction of normothermic regional perfusion (NRP) in controlled donation after circulatory determination of death (cDCDD) protocols is by some regarded as controversial and ethically troublesome. One of the main concerns that opponents have about introducing NRP in cDCDD protocols is that reestablishing circulation will negate the determination of death by circulatory criteria, potentially resuscitating the donor. In this article, I argue that this is not the case. If we take a closer look at the concept of death underlying the circulatory criterion for determination of death, we find that the purpose of the criterion is to show whether the organism as a whole has died. I argue that this purpose is fulfilled by the circulatory criterion in cDCDD protocols, and that applying NRP does not negate the determination of death or resuscitate the donor.


Assuntos
Morte , Obtenção de Tecidos e Órgãos , Humanos , Obtenção de Tecidos e Órgãos/ética , Perfusão , Doadores de Tecidos/ética , Ressuscitação/ética , Circulação Sanguínea
15.
Am J Bioeth ; 24(6): 34-37, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829600

RESUMO

An adult university hospital ethics committee evaluated a proposed TA-NRP protocol in the fall of 2018. The protocol raised ethical concerns about violation of the Uniform Determination of Death Act and the prohibition known as the Dead Donor Rule, with potential resultant legal consequences. An additional concern was the potential for increased mistrust by the community of organ donation and transplantation. The ethics committee evaluated the responses to these concerns as unable to surmount the ethical and legal boundaries and the ethics committee declined to endorse the procedure. These concerns endure.


Assuntos
Comissão de Ética , Perfusão , Obtenção de Tecidos e Órgãos , Humanos , Obtenção de Tecidos e Órgãos/ética , Doadores de Tecidos/ética , Morte Encefálica , Transplante de Órgãos/ética , Transplante de Órgãos/legislação & jurisprudência , Morte
16.
J Cardiothorac Vasc Anesth ; 38(9): 2047-2058, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38981770

RESUMO

Heart transplantation is the definitive treatment for refractory, end-stage heart failure. The number of patients awaiting transplantation far exceeds available organs. In an effort to expand the donor pool, donation after circulatory death (DCD) heart transplantation has garnered renewed interest. Unlike donation after brain death, DCD donors do not meet the criteria for brain death and are dependent on life-sustaining therapies. Procurement can include a direct strategy or a normothermic regional perfusion, whereby there is restoration of perfusion to the organ before explantation. There are new developments in cold storage and ex vivo perfusion strategies. Since its inception, there has been a steady improvement in post-transplant outcomes, largely attributed to advancements in operative and procurement strategies. In this narrative review, the authors address the unique considerations of DCD heart transplantation, including withdrawal of care, the logistics of procuring and resuscitating organs, outcomes compared with standard donation after brain death, and ethical considerations.


Assuntos
Transplante de Coração , Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Humanos , Transplante de Coração/métodos , Obtenção de Tecidos e Órgãos/métodos , Morte Encefálica , Preservação de Órgãos/métodos , Morte
17.
Biochem Genet ; 62(1): 156-175, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37296335

RESUMO

Neuropilin-1 (NRP1) which is a main transmembrane cell surface receptor acts as a host cell mediator resulting in increasing the SARS-Cov-2 infectivity and also plays a role in neuronal development, angiogenesis and axonal outgrowth. The goal of this study is to estimate the impact of single nucleotide polymorphisms (SNPs) in the NRP1 gene on the function, structure and stabilization of protein as well as on the miRNA-mRNA binding regions using bioinformatical tools. It is also aimed to investigate the changes caused by SNPs in NRP1 on interactions with drug molecule and spike protein. The missense type of SNPs was analyzed using SIFT, PolyPhen-2, SNAP2, PROVEAN, Mutation Assessor, SNPs&GO, PhD-SNP, I-Mutant 3.0, MUpro, STRING, Project HOPE, ConSurf, and PolymiRTS. Docking analyses were conducted by AutoDock Vina program. As a result, a total of 733 missense SNPs were determined within the NRP1 gene and nine SNPs were specified as damaging to the protein. The modelling results showed that wild and mutant type amino acids had some different properties such as size, charge, and hydrophobicity. Additionally, their three-dimensional structures of protein were utilized for confirmation of these differences. After evaluating the results, nine polymorphisms rs141633354, rs142121081, rs145954532, rs200028992, rs200660300, rs369312020, rs370117610, rs370551432, rs370641686 were determined to be damaging on the structure and function of NRP1 protein and located in conserved regions. The results of molecular docking showed that the binding affinity values are nearly the same for wild-type and mutant structures support that the mutations carried out are not in the focus of the binding site, therefore the ligand does not affect the binding energy. It is expected that the results will be useful for future studies.


Assuntos
COVID-19 , Polimorfismo de Nucleotídeo Único , Humanos , Simulação de Acoplamento Molecular , SARS-CoV-2/genética , Sítios de Ligação/genética
18.
Environ Toxicol ; 39(2): 942-951, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37972228

RESUMO

The present study investigated the effect of tretinoin (2,4-difluoro-phenyl) triazole (TDFPT) on the growth and proliferation of Kyse-270 and EC9706 esophageal carcinoma cells and explored the underlying mechanism. The results demonstrated that TDFPT treatment of Kyse-270 and EC9706 cells led to a dose-dependent reduction in cell proliferation. Colony formation was significantly (p < .05) reduced in Kyse-270 and EC9706 cells on treatment with various concentrations of TDFPT. In TDFPT-treated Kyse-270 and EC9706 cells, the expression of Bcl-2 protein showed a remarkable decrease, whereas the level of Bax protein was found to be higher compared with the control cells. Cell invasion showed a prominent decrease in Kyse-270 and EC9706 cells on treatment with TDFPT. Treatment with TDFPT led to a prominent suppression in the expression of MMP-9 and NRP2 in Kyse-270 and EC9706 cells. In silico studies using the AutoDock Vina and discovery studio software revealed that various confirmations of TDFPT bind to NRP2 protein with the affinity ranging from -8.6 to -6.1 kcal/mol. It was found that the TDFPT interacts with NRP2 protein by binding to alanine (ALA A:295), proline (PRO A:306), glutamine (GLN A:307), and isoleucine (ILE A:293) amino acid residues. In summary, TDFPT exposure suppresses esophageal carcinoma cell proliferation, inhibits colony formation ability, and activates apoptotic pathway. Thus, TDFPT acts as an effective antiproliferative agent for esophageal carcinoma cells and needs to be investigated further as chemotherapeutic molecule.


Assuntos
Carcinoma , Neoplasias Esofágicas , Humanos , Neuropilina-2/uso terapêutico , Proteínas Reguladoras de Apoptose , Tretinoína/farmacologia , Tretinoína/uso terapêutico , Triazóis/farmacologia , Linhagem Celular Tumoral , Neoplasias Esofágicas/metabolismo , Proliferação de Células , Apoptose
19.
Int J Mol Sci ; 25(17)2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39273582

RESUMO

Angiotensin-converting enzyme 2 (ACE2) is considered a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor of high importance, but due to its non-ubiquitous expression, studies of other proteins that may participate in virus internalisation have been undertaken. To date, many alternative receptors have been discovered. Their functioning may provide an explanation for some of the events observed in severe COVID-19 that cannot be directly explained by the model in which ACE2 constitutes the central point of infection. Diabetes mellitus type 2 (T2D) can induce severe COVID-19 development. Although many mechanisms associated with ACE2 can lead to increased SARS-CoV-2 virulence in diabetes, proteins such as basigin (CD147), glucose-regulated protein 78 kDa (GRP78), cluster of differentiation 4 (CD4), transferrin receptor (TfR), integrins α5ß1/αvß3, or ACE2 co-receptors neuropilin 2 (NRP2), vimentin, and even syalilated gangliosides may also be responsible for worsening the COVID-19 course. On the other hand, some others may play protective roles. Understanding how diabetes-associated mechanisms can induce severe COVID-19 via modification of virus receptor functioning needs further extensive studies.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Diabetes Mellitus Tipo 2 , Chaperona BiP do Retículo Endoplasmático , SARS-CoV-2 , COVID-19/metabolismo , COVID-19/virologia , COVID-19/complicações , Humanos , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/metabolismo , Chaperona BiP do Retículo Endoplasmático/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/virologia , Internalização do Vírus , Receptores Virais/metabolismo
20.
Cancer Metastasis Rev ; 41(3): 771-787, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35776228

RESUMO

Neuropilins (NRPs) are transmembrane proteins involved in vascular and nervous system development by regulating angiogenesis and axon guidance cues. Several published reports have established their role in tumorigenesis. NRPs are detectable in tumor cells of several cancer types and participate in cancer progression. NRP2 is also expressed in endothelial and immune cells in the tumor microenvironment and promotes functions such as lymphangiogenesis and immune suppression important for cancer progression. In this review, we have taken a comprehensive approach to discussing various aspects of NRP2-signaling in cancer, including its regulation, functional significance in cancer progression, and how we could utilize our current knowledge to advance the studies and target NRP2 to develop effective cancer therapies.


Assuntos
Neoplasias , Neuropilina-2 , Transdução de Sinais , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Neovascularização Patológica , Neuropilina-2/metabolismo , Neuropilinas/metabolismo , Microambiente Tumoral
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